AERCO Esteem O&M Manual - Manual (Page 71)

65
Check Expansion Tank
Check Expansion Tank
Refer to Section IV - Boiler Piping for recom-
mended location of the expansion tank and
air eliminators.
Closed -Type Tank:
• Ensure tank is partially filled with water
leaving an air gap as a cushion. Refer
to the manufacturer’s instruction for
proper fill level.
• Ensure the tank is fitted with a device
that reduces gravity circulation of air-
saturated tank water back into the sys-
tem. This device prevents air from bub-
bling up through the water as it returns
from the system.
• Ensure no automatic air vents are
used in the system. This will allow air
to escape from the system instead of
returning to the tank.
Diaphragm Tank:
• Ensure the system contains a minimum
of one automatic air vent. Recommended
location of the air vent should be atop an
air eliminator.
• Remove the tank from the system and
check the charge pressure. For residen-
tial applications the charge pressure is
typically 12 psig. If tank does not hold
a charge pressure, then the membrane
is damaged and the tank should be
replaced.
Check Boiler Relief Valve
Inspect the relief valve and lift the lever to ver-
ify flow at least annually or as recommended
on the warning tag of the valve.
WARNING!
B
EFORE MANUALLY OPERATING THE PRESSURE
RELIEF VALVE
,
ENSURE THE DISCHARGE PIPING
IS DIRECTED TO A SUITABLE PLACE OF DISPOS
-
AL TO AVOID A POTENTIAL SCALD HAZARD
. T
HE
DISCHARGE PIPING MUST BE FULL SIZE WITHOUT
RESTRICTION AND INSTALLED TO PERMIT COM
-
PLETE DRAINAGE OF BOTH THE VALVE AND LINE
.
If when closed, the valve fails to seat properly
or continually weeps and it has been deter-
mined that the cause is not system over-pres-
surization due to an undersized or waterlogged
expansion tank, replace the relief valve.
Inspect Ignition Electrode
1. Remove the ignition electrode from the
burner mounting plate.
2. Remove any white oxides on the electrode
using fine grit sandpaper or steel wool. If
the electrode does not clean to a satisfac-
tory condition, replace the ignitor .
3. Ensure the gasket is in good condition
and correctly positioned, replace gasket if
necessary.
GF-125